Obama Administration Proposes Tougher Rules on Soot Pollution

In another case of environmental rules becoming election fodder, the Obama administration on Friday proposed tighter restrictions on soot, a pollutant caused mainly by smokestacks and diesel engines.

It had been called “the sleeping giant of clean-air issues” by Frank O’Donnell, head of the activist group Clean Air Watch. And while little was made of it until now, Republicans and industry were quick to pounce on it as more red tape in a weak economy.

The proposed Environmental Protection Agency rule would set the maximum allowable standard for soot in a range of 12 to 13 micrograms per cubic meter of air. The current annual standard, last revised in 1997, is 15 micrograms per cubic meter.